Fighting pushes on through the night in downtown Cairo - and anger at Egyptian President Mohamed Mursi is on the rise.
Riot police fire tear gas into crowds of demonstrators, who respond by throwing stones.
The widespread anger stems from a declaration Mursi made last Thursday that extends his powers while disempowering his opponents.
Tuesday's protests are set to be big - with massive marches and rallies expected to converge in Tahrir Square.
In the early hours anticipation is high - and so is frustration at Mursi's divisive power grab.
(SOUNDBITE) (English) DEMONSTRATOR HAMDY DARDEEL, SAYING:
"The decree that President Mursi issued isn't within his rights and he needs to understand this. Every law professor in the country has said that it isn't within his rights, so he needs to understand this and know that the people have divided."
Mursi has been accused of anointing himself a modern-day pharaoh - while many in the Square have compared him with ousted leader Hosni Mubarak.
The Muslim Brotherhood and other Islamist parties said they had postponed a counter-rally on Tuesday in an effort to avoid bloodshed.